unconfirmed_users = ['a','b','c']
confirmed_users = []

while unconfirmed_users:
    current_user = unconfirmed_users.pop()
    print(f"Verifying user:{current_user.title()}")
    confirmed_users.append(current_user)
print(unconfirmed_users)

print("\nThe following users have been confirmed:")
for confirmed_user in confirmed_users:
    print(confirmed_user.title())